Investigation on aerodynamic interference mechanism of a contra-rotating propfan under take-off condition

Abstract Contra-rotating propfan (CRP) produce significant aerodynamic interference between the front and rear blades. The interaction effect of the front blade on the rear blade consists of two parts: the impact of the wake of the front blade and the tip vortex on the leading edge of the rear blade. The cutting effect of the rear blade on the wake section and tip vortex structure of the front blade. The combined action causes the pressure fluctuation of the rear blade, especially in the tip, the pressure fluctuation on the suction surface is more significant. The effect of the rear blade on the front blade is mainly reflected in that the potential flow effect of the rear blade leads to a relatively obvious pressure fluctuation on the pressure surface of the front blade. Under the potential flow effect, the pressure disturbance of the suction surface of the rear blade propagates upstream, which affects the pressure of the front blade pressure surface and makes its pressure distribution tends to that of the rear blade suction surface.